60 



FAUNA ANTIQUA SIVALENSIS. 



Meyer described tinder the same name a fragment of the 

 npper jaw of a young mastodon, from the celebrated deposit 

 of Eppelsheim, containing the three first molars in situ} 

 After considering the characters indicated by Croizet and 

 Jobert, he states that M. Arvernensis is distinguished from 

 M. maximus (M. Ohioticus), M. angustidens, and all the other 

 species then known, by the circumstance that the third 

 molar in the order of antero-posterior succession has the 

 crown divided into four ridges, while the same tooth in the 

 other species presents only three ridges. In a subsequent 

 memoir, on the fossil remains of G-eorgensmiind,^ von Meyer 

 figured and described several mastodontine grinders, which 

 he referred to the true M. angustidens of Cuvier, and which 

 confirmed the constancy of the differential character between 

 that species and M. Arvernensis, in the numerical division 

 and form of the crown ridges, as pointed out by him in his 

 previous memoir. This was the first stej) towards a satis- 

 factory determination of the species, as distinct from M. 

 angustidens ; and a great mass of additional materials, con- 

 firming the same inference, was soon aftei-wards brought to 

 light by Dr. Kaup ; but, in the interim, new observations, of 

 great interest, were made upon the mastodon of ISTorth 

 America, which gave an entirely different character to the 

 investigation from this date. 



No susj)ieion appears to have been entertained before this 

 time, that any of the mastodons, more than the existing 

 elephants, possessed tusks in the lower jaw. Cuvier ex- 

 pressly af&rms their absence,^ although, as has been observed 

 by Professor Owen,* he figiu'ed in the original memoir in the 

 ' Annales du Museum,' and in the first edition of the ' Osse- 

 mens Possiles,' a lower jaw of an adult Mastodon, showing 

 what appears to be the alveolus of a persistent inferior tusk. 

 Early in 1830, a memoir by Dr. Godman was read to the 

 American Philosophical Society,^ upon a mastodontoid lower 

 jaw, with two small tusks, which he described as character- 

 izuig a distmct proboscidean genus, under the name of 

 Tetracaulodon. This jaw belonged to a young animal, and 

 showed four molars on each side, the anterior two of which 

 Godman considered to belong to the ' milk,' and the rest to 

 the permanent series. These teeth resembled, in every 

 respect, molars of the same size, in other specimens of the 



' Hermann von Meyer, ' Uelier Mas- 

 todon Arvernensis bei Eppelsheim.' Nov. 

 Act. Acad. Lcop. Carol. Natui'. Curios. 

 1829. Vol. XV. p. 113. 



- Museum Senckenborgianum. Die 

 fossilen Zahne und Knochen von Geor- 



gensmiind, 1834, p. 33, tab. 1 and 3. 



" Oss. Foss. torn. i. p. 233. 



* Owen, ' Odontography,' p. 619. 



^ Godman, ' Americ. Phil. Trans.' New 

 Ser. vol. iii. p. 478. ' Tetracaulodon 

 Mastodontoi'deum,' 



